Week 27 – July 4-8

2011 MOSQUITO REPORT: WEEK 27

Report based on data collected from traps deployed the week of July 4, 2011 through July 8, 2011. Report prepared by John Smith, Chan Suom, M.S., and Nate Boonisar.

1. CURRENT MOSQUITO ACTIVITY/TREND

CDC Light Traps:
Host-seeking mosquito activity was mixed throughout Norfolk County this week, with most towns indicating below average biting levels. Avon, Dedham, Foxboro, parts of Sharon, Stoughton, and parts of Walpole reported average levels of activity; whereas Medway, Millis, Norfolk, Quincy, parts of Sharon, parts of Walpole, and Wrentham collected higher than average numbers of host-seeking mosquitoes.

Gravid Traps:
Once again this week, gravid mosquito activity has continued the upward trend of having a higher than average population. Only Millis and Randolph had lower than average gravid mosquito activity.

2. CURRENT PREDOMINANT SPECIES

CDC Light Traps:
Coquillettidia perturbans continues to be the most populous species of mosquitoes in most towns. Ochlerotatus canadensis are at large in Sharon and Millis, whereas Aedes vexans is more abundant than usual in Franklin, Sharon, Walpole, Weymouth, and Wrentham. Oc. sollicitans are starting to appear in larger numbers in Quincy.

Gravid Traps:
Gravid Culex pipiens/restuans mosquitoes continue this week with a higher than average collection. Oc. japonicus numbers are average to lower than average for the week.

3. COMPARISON TO PREVIOUS SEASON

As stated last week, mosquitoes benefit from this weather activity of on and off rain every few days or so; and this is reflected by the higher than average occurrences of Oc. canadensis, Ae. vexans, and Co. perturbans in the aforementioned towns. Co. perturbans continues the trend of being very plentiful around the 4th of July and will presumably continue in high numbers for a few more weeks if the historical data is any indication. Oc. sollicitans has started to appear in larger numbers in Quincy. Psorophora ferox populations are lower than expected for this time of year, especially in Canton.

4. WEATHER SUMMARY

This first half of this week was very warm and rather humid. A storm system moved through on Friday into early Saturday bringing widespread heavy showers and thunderstorms to the area with varying amounts of rainfall. Northern sections received the least with amounts near ½ inch, while areas along the southern border received 1.5 to 2 inches (1.77” in Stoughton). Cooler and drier weather returned by the weekend.

Total weekly rainfall: 0.71 inches (+0.01 in.)
Total Monthly rainfall: 0.83 inches (-0.07 in.)
Total Yearly rainfall: 23.46 inches (+1.28 in.)

5. NUMBER OF REQUESTS FOR SERVICE

NCMCP received 3,834 calls year to date for service as of 7/8/11. NCMCP received 415 calls for service this week.

6. MCP/COMMISSION RESPONSE

NCMCP continues “area wide” ground ULV applications in high request areas and in areas where collection data indicate a need. Rain basin treatments have begun with a concentration in urban areas where West Nile virus has been collected historically. As is noted in Chan’s report, higher levels of Culex(PRE) have been collected in gravid traps. Rain basin treatments in the eastern areas where gravid traps are showing high levels of Culex have been prioritized. NCMCP has conducted some ground larviciding in coastal areas.

Contact

144 Production Rd, Suite C

Walpole, MA 02081

Office: (781) 762-3681
Fax: (781) 769-6436